This application requests funds to purchase and manage the Applied Precision Delta Vision deconvolution microscope system and the Zeiss Nonlinear Optics 510 Multiphoton microscope system that will constitute the Neuroscience Imaging Core at the. University of California, San Diego. Microscopic imaging is becoming an ever important aspect of neuroscience studies, and the requested systems will utilize the imaging strengths of deconvolution microscopy that excels in dissociated cell work, and multiphoton microscopy that excels in analysis in whole tissue. The proposed research involves neuronal stem-cell differentiation, migration, axon guidance, injury repair, comparative anatomy, degenerative disease and developmental biology, and together requires time lapse imaging, deep tissue light penetration, three dimensional reconstruction, analysis of multiple cells using two or more fluorophores to enable co localization, photoablation capabilities, environmental control, with minimization of photodamage. The requested systems were chosen because of their high image quality, excellent live-cell imaging capabilities and most importantly their ease of use, which will be critical for a multi-user Core. The Delta Vision system employs a standard epifluorescent microscope with highly optimized wide field illumination and x-y z-time series capabilities. The constrained iterative deconvolution is quantitative, conserves the maximum amount of data, and affords high sensitivity and resolution with minimum illumination, thus minimizing phototoxicity. The Zeiss system employs a Ti: Sapphire laser to provide tunable infrared illumination with absolute beam control over the entire field, and x-y-z time series capabilities that allows for imaging of neural tissue to depths of 300-500 pM. This Core will draw off of the expertise of the larger UCSD Medical School Imaging Core that combines conventional light, fluorescent and confocal microscopy, stereology, needle microinjection, tissue culture and image processing with an experienced staff of on-hand microscopists to provide training and technical expertise to users for each of the services offered. The flexibility, dynamic range, sensitivity, multiple cell sampling, rapid three-dimensional imaging properties and ease of use of the requested instruments is essential for the proposed, NINDS-funded work that has important implications for multiple nervous system diseases.